This invention relates to an airbag apparatus for a vehicle such as an automobile, particularly to a construction for installing an inflator in the apparatus.
A customary airbag apparatus for an automobile generally has a construction as shown in FIG. 1 sketchily and disclosed in Japanese Laid-Open Patent Publication HEI 5-201302 for example.
In the apparatus, an airbag 01 is fixed to a retainer 02, folded up and housed in a cover capable of opening.
And an inflator 03 which is a gas generator is pushed into the airbag 01 folded up within the cover through an opening portion of the retainer 02 and fixed to the airbag together with the retainer 02 or singly.
A portion of the airbag 01 to which the retainer 02 is fixed serves also as a fixing portion of the inflator 03, and there is provided a fixing member 04 such as a reinforce cloth or a flame-proof cloth on the inner surface of the portion. Suspension strings 05 each with an end fixed to the fixing member 04 extend within the airbag 01 and the outer end of the string 05 is fixed to an apex portion of the airbag facing to the fixing member 04 where a man comes to contact with when the airbag is inflated. The suspension strings 05 prescribe the shape of the inflated airbag.
When the inflator acts to generate a gas within the airbag 01, the airbag 01 expands to the outside tearing the cover due to its inner pressure and develops into a predetermined shape prescribed by the suspension strings 05.
Since the inflator 03 is fixed to the retainer 02 directly or indirectly as described above, it is necessary to select a construction and a material for the retainer 02 capable of enduring reaction force, heat or the like under action of the inflator 03, and therefore the cost of the retainer increases.
Further, when the inflator is attached to the retainer, a complicated progress of work such as tightening by screw is needed and since various parts for attachment is necessary the weight is increased. In addition, sealing against a gas leakage from a portion where the inflator 03 is fixedly contacted with the retainer 02 is also complicated and there is a fear that an unnecessary gas leakage on inflation of the airbag may make the inflation incomplete.